In order to determine which country smokes the most marijuana, the organization looks at a variety of statistics. These include how many of the adult population (15 to 65-years-old) have smoked the drug in the last 12 months (or the last 12 months for which the organization has statistics for).

We've taken this set of statistics and used it to rank the top 20 pot-smoking countries in the EU. We've also included figures showing what percentage of each country's adults have smoked marijuana during their lifetime.